How many possible 3-digit area codes exist If 0 can't be the first digit, but digits can repeat?

A total of _?_ different 3-digit area codes exist.​

Step-by-step explanation:

If all numbers were used in each of the 3 places it would be 10^3= 1000.

Since 0s and 1s are not used as beginning numbers and 9 is not assigned to the middle it is as follows:

n3 - 3(n^2) = 700

I reread the question. If you mean “if" any digit could be used in any place , it would be 10^3= 1000.

any options?

step-by-step explanation:

an

y = 6x -3y -12

y +3y +12 = 6x

=> . x = { 2y / 3 +2 } this is equation of line in terms of x

=> . if line meets the x-axis the co-ordinates of meeting point would be ( x , 0 )

=> . x = 2 ( 0 ) / 3 + 2

=> . x = 2

so, the point is ( 2 , 0 )